Polyamide resins are widely in use as materials for various parts, such as those for industrial materials, automobiles, electrics and electronics, industrial use, etc. due to them having superior sliding properties, molding processing properties, mechanical properties, and chemical resistance properties.
Compositions in which a solid lubricant such as a fluorine series resin, graphite, and molybdenum disulfide is blended into a polyamide resin and kneaded are known as a means for further improving the sliding properties of polyamide resin. Lately, conversion of metal components into resin components is accelerating in the automotive field, the electric and electronic field, etc. Particularly recently, molding materials having more superior sliding properties as well as superior mechanical properties such as toughness and impact resistance are in demand in the automotive field, from the viewpoints of weight reduction to improve fuel efficiency, cost reduction, and streamlining of assembly processes.
For example, International Patent Publication No. WO 2013/047625 proposes a resin composition as a technique for further improving the sliding properties of a polyamide resin. In this resin composition, a hard resin and a fluorine series resin having close melting points are melt kneaded under high shear conditions, to adjust the maximum dispersed particle diameter of the fluorine series resin to be 950 nm or less.
In addition, Japanese Unexamined Patent Publication No. 2011-84679 proposes a sliding member for a power transmission guide formed by a resin composition. The resin composition is formed by blending a fluorine series resin, which has been modified by electron beam irradiation, into a base material resin, and then conducting reactive extrusion.
Further, Japanese Unexamined Patent Publication No. 2012-102189 proposes a composition having improved sliding properties. This composition is produced by blending a siloxane compound and a fluorine series resin into a polyamide resin, and then melt kneading.